The present invention relates generally to the field of devices and methods for delivering substances to bone. More particularly, the present invention concerns devices and methods for performing a kyphoplasty procedure to treat conditions of the spine.
Kyphoplasty is a procedure used to treat painful compression fractures in the spine. When the compression fracture occurs, part of a spine bone collapses. Compression fractures are often caused by osteoporosis resulting in softening and weakening of the vertebrae. Small fractures in the bone can eventually cause the vertebra to collapse, thereby creating the spinal compression fracture. Compression fractures can occur suddenly, and severe pain usually results from the fracture. Most often, compression fractures occur in the softer bone of the front of the vertebra. When the front part of the bone collapses, a wedge-shaped vertebra may result. Many compression fractures in the front of the vertebrae may eventually cause kyphosis, which is a hump-like curvature of the spine (sometimes referred to as a dowager's hump). Other symptoms of compression fractures include tenderness at the spine, back pain that gets worse with walking, but usually not felt while resting, and loss of height.
Conventional methods of performing a kyphoplasty procedure make use of balloon like device to create space in the bone to compensate for the deformity caused by the compression fracture, and then filling the void with bone cement. More specifically, one method includes advancing a biopsy needle into the pedicle of the vertebra, under fluoroscopic guidance, and inserting a cannula over the needle. Once the cannula is positioned, the needle is removed from the pedicle. An inflatable catheter or balloon tamp is then inserted through the cannula and into the collapsed portion of the vertebra. The balloon is then slowly inflated to create a void in the bone. Once the void is created, the inflatable catheter or balloon tamp is removed in preparation to receive the bone cement. A bone cement delivery device, such as a delivery needle is then inserted into the cannula and the bone cement is delivered to the void created by the inflated balloon. When the bone cement has cured, the cannula and the delivery device is removed, to complete the procedure.
The conventional methods, such as that described above, involve multiple steps that require the introduction and removal of various tools throughout the process. Not only is this process cumbersome, but also time consuming. If the procedure is necessary for multiple vertebrae, the time and the complexity of the process multiplies. Also, if additional space needs to be created in the vertebra before the procedure is complete, the cement delivery device must be removed and replaced by the inflatable device, which is re-inflated, and then the delivery device re-introduced to deliver the remainder of the cement.